JAVA 比较两张图片的相似度

原文：http://liuguihua0823.iteye.com/blog/1178118#bc2395917

import java.awt.image.BufferedImage;  
import java.io.File;  
import javax.imageio.ImageIO;  
  
/** 
 * 比较两张图片的相似度 
 * @author Guihua 
 * 
 */  
public class BMPLoader {  
    // 改变成二进制码  
    public static String[][] getPX(String args) {  
        int[] rgb = new int[3];  
  
        File file = new File(args);  
        BufferedImage bi = null;  
        try {  
            bi = ImageIO.read(file);  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
  
        int width = bi.getWidth();  
        int height = bi.getHeight();  
        int minx = bi.getMinX();  
        int miny = bi.getMinY();  
        String[][] list = new String[width][height];  
        for (int i = minx; i < width; i++) {  
            for (int j = miny; j < height; j++) {  
                int pixel = bi.getRGB(i, j);  
                rgb[0] = (pixel & 0xff0000) >> 16;  
                rgb[1] = (pixel & 0xff00) >> 8;  
                rgb[2] = (pixel & 0xff);  
                list[i][j] = rgb[0] + "," + rgb[1] + "," + rgb[2];  
  
            }  
        }  
        return list;  
  
    }  
      
    public static void compareImage(String imgPath1, String imgPath2){  
        String[] images = {imgPath1, imgPath2};  
        if (images.length == 0) {  
            System.out.println("Usage >java BMPLoader ImageFile.bmp");  
            System.exit(0);  
        }  
  
        // 分析图片相似度 begin  
        String[][] list1 = getPX(images[0]);  
        String[][] list2 = getPX(images[1]);  
        int xiangsi = 0;  
        int busi = 0;  
        int i = 0, j = 0;  
        for (String[] strings : list1) {  
            if ((i + 1) == list1.length) {  
                continue;  
            }  
            for (int m=0; m<strings.length; m++) {  
                try {  
                    String[] value1 = list1[i][j].toString().split(",");  
                    String[] value2 = list2[i][j].toString().split(",");  
                    int k = 0;  
                    for (int n=0; n<value2.length; n++) {  
                        if (Math.abs(Integer.parseInt(value1[k]) - Integer.parseInt(value2[k])) < 5) {  
                            xiangsi++;  
                        } else {  
                            busi++;  
                        }  
                    }  
                } catch (RuntimeException e) {  
                    continue;  
                }  
                j++;  
            }  
            i++;  
        }  
  
        list1 = getPX(images[1]);  
        list2 = getPX(images[0]);  
        i = 0;  
        j = 0;  
        for (String[] strings : list1) {  
            if ((i + 1) == list1.length) {  
                continue;  
            }  
            for (int m=0; m<strings.length; m++) {  
                try {  
                    String[] value1 = list1[i][j].toString().split(",");  
                    String[] value2 = list2[i][j].toString().split(",");  
                    int k = 0;  
                    for (int n=0; n<value2.length; n++) {  
                        if (Math.abs(Integer.parseInt(value1[k]) - Integer.parseInt(value2[k])) < 5) {  
                            xiangsi++;  
                        } else {  
                            busi++;  
                        }  
                    }  
                } catch (RuntimeException e) {  
                    continue;  
                }  
                j++;  
            }  
            i++;  
        }  
        String baifen = "";  
        try {  
            baifen = ((Double.parseDouble(xiangsi + "") / Double.parseDouble((busi + xiangsi) + "")) + "");  
            baifen = baifen.substring(baifen.indexOf(".") + 1, baifen.indexOf(".") + 3);  
        } catch (Exception e) {  
            baifen = "0";  
        }  
        if (baifen.length() <= 0) {  
            baifen = "0";  
        }  
        if(busi == 0){  
            baifen="100";  
        }  
  
        System.out.println("相似像素数量：" + xiangsi + " 不相似像素数量：" + busi + " 相似率：" + Integer.parseInt(baifen) + "%");  
  
    }  
  
    public static void main(String[] args){  
        BMPLoader.compareImage("E:\12.bmp", "E:\1.bmp");  
    }  
} 

package com.rd.p2p.additional.redisCaptcha.util;

import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;

import com.octo.captcha.service.CaptchaServiceException;
import com.rd.p2p.common.util.jcaptcha.CaptchaServiceSingleton;

public class ResponseUtil {
    
    private static Logger logger= Logger.getLogger(ResponseUtil.class);

    public static boolean sendMessageNoCache(HttpServletResponse response, String message) {
        response.setContentType("text/html;charset=UTF-8");
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("Cache-Control", "no-store");
        response.setDateHeader("Expires", 0);
        response.setHeader("Pragma", "no-cache");
        StringBuffer sb = new StringBuffer();
        try {
            PrintWriter writer = response.getWriter();
            sb.append(message);
            writer.write(sb.toString());
            response.flushBuffer();
            return true;
        } catch (Exception e) {
            logger.error("直接推送字符串错误", e);
            return false;
        }
    }

    public static boolean sendJSON(HttpServletResponse response, Object obj){
        response.setContentType("text/json;charset=UTF-8");
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("Cache-Control", "no-store");
        response.setDateHeader("Expires", 0);
        response.setHeader("Pragma", "no-cache");
        StringBuffer sb = new StringBuffer();
        try {
            PrintWriter writer = response.getWriter();
            sb.append(JSONUtil.toJSON(obj));
            writer.write(sb.toString());
            response.flushBuffer();
            return true;
        } catch (Exception e) {
            logger.error("直接推送JSON数据错误", e);
            return false;
        }
    }

    public static boolean sendJSONP(HttpServletResponse response, String callBack, Object obj){
        response.setContentType("application/javascript;charset=UTF-8");
        response.setHeader("Cache-Control", "no-cache");
        response.setHeader("Cache-Control", "no-store");
        response.setDateHeader("Expires", 0);
        response.setHeader("Pragma", "no-cache");
        StringBuffer sb = new StringBuffer();
        try {
            PrintWriter writer = response.getWriter();
            sb.append(JSONUtil.toJSONP(callBack, obj));
            writer.write(sb.toString());
            response.flushBuffer();
            return true;
        } catch (Exception e) {
            logger.error("直接推送JSONP数据错误", e);
            
            return false;
        }
    }

    public static void sendImg(HttpServletResponse response, BufferedImage buffImg, String mimeType, String fileName, String extName)  throws IOException {
//        OutputStream out= null;
//        response.setContentType(mimeType);
//        response.setHeader("Content-Disposition", String.format("attachment;filename=%s.%s", fileName, extName));
//        try {
//            out= response.getOutputStream();
//            ImageIO.write(buffImg, extName, out);
////            BufferedInputStream buffIn= new BufferedInputStream(in);
////            BufferedOutputStream buffOut= new BufferedOutputStream(out);
////            byte buff[]= new byte[4096];//申请缓冲区
////            int size= buffIn.read(buff);//初始化读取缓冲
////            while (size!= -1) {
////                buffOut.write(buff, 0, size);//输出缓冲数据
////                size= buffIn.read(buff);//继续读取数据
////            }
////            buffIn.close();//关闭输入流
////            buffOut.flush();//清空输出流
////            buffOut.close();//关闭输出流
//            return true;
//        } catch (IOException e) {
//            logger.error("直接推送图片错误", e);
//            return false;
//        }
        
        
        
        
        
        
        response.setHeader("Cache-Control", "no-store");
        response.setHeader("Pragma", "no-cache");
        response.setDateHeader("Expires", 0);
        response.setContentType("image/jpeg");
        ServletOutputStream out = response.getOutputStream();
        try {
//            String captchaId = request.getSession(true).getId();
//            LOGGER.info("当前生产验证码的sessionId为: "+captchaId);
//            BufferedImage challenge = (BufferedImage) CaptchaServiceSingleton.getInstance().getChallengeForID(
//                    captchaId, request.getLocale());
            ImageIO.write(buffImg, "jpg", out);
            out.flush();
        } catch (CaptchaServiceException e) {
        } finally {
            out.close();
        }
        
        
        
        
        
        
        
    }

}